
.index-img img{
    margin-left: 250px;
    padding: 6px;
}
#nav{
    width:100% ;
    height: 40px;
    text-align: center;
    border-top:3px solid red ;
    margin-bottom: 20px;
    border-bottom:0.3px solid #ccc ;
}
#nav ul{
    display: inline-block;
}
#nav ul li{
    font-size: 18px;
    font-family: 宋体;
    display: inline-block;
}
#nav ul li a{
    text-decoration: none;
}